Chamber, lid, and leak tester

The present invention relates to a chamber, a lid, and a leak tester.

A leak tester is used to inspect a workpiece having an opening for gas leaks and the like. In a known leak tester of this type, the workpiece is positioned in a chamber such that the opening is in a predetermined position, whereupon a nozzle is attached to the opening of the workpiece and a tracer gas is supplied to the space inside the workpiece through the nozzle (see Japanese Unexamined Patent Application Publication No. 2013-134098).

Japanese Unexamined Patent Application Publication No. 2013-134098 describes a chamber in which a housing space for housing the workpiece is formed by joining first and second chamber constituent bodies to each other. Japanese Unexamined Patent Application Publication No. 2013-134098 indicates that the housing space is formed in a shape corresponding to the workpiece, and the workpiece is positioned within the chamber by partially supporting the workpiece using the inner surface of the first chamber constituent body forming the housing space.

The chamber described in Japanese Unexamined Patent Application Publication No. 2013-134098 is designed to correspond to the size of the workpiece. Therefore, according to the configuration described in Japanese Unexamined Patent Application Publication No. 2013-134098, a different chamber must be prepared every time the size of the workpiece changes. Accordingly, the chamber described in Japanese Unexamined Patent Application Publication No. 2013-134098 lacks versatility.

The present invention has been designed on the basis of the circumstances described above, and an object thereof is to provide a chamber in which workpieces of different sizes can be positioned.

(1) A chamber according to an aspect of the present invention is a chamber for a leak tester, the chamber housing in the interior thereof a workpiece having an opening, the chamber including: a first member having a recess that forms a housing space for the workpiece; a second member adapted to close an open end of the recess; and a positioning mechanism for positioning the workpiece within the housing space such that the opening is in a predetermined position, wherein the positioning mechanism holds the workpiece apart from the first member and the second member.

(2) In (1), preferably, the positioning mechanism includes a spacer plate and a pushing body respectively disposed on the second member, the spacer plate is interposed between the workpiece and an inner surface of the recess, the pushing body is disposed so as to face the spacer plate with the workpiece therebetween, and the pushing body is adapted to push the workpiece toward the spacer plate.

(3) In (2), the pushing body preferably pushes the spacer plate via the workpiece such that the spacer plate is appressed to the inner surface of the recess.

(4) In (2) or (3), preferably, the positioning mechanism includes a connecting portion for connecting the spacer plate to the second member, and the spacer plate is held by the connecting portion in a cantilevered manner.

(5) In (4), the connecting portion preferably includes a swinging mechanism adapted to swing the spacer plate, and a fixing mechanism adapted to maintain an interval between the spacer plate and the workpiece.

(6) In any of (2) to (5), the second member is preferably adapted to close the open end of the recess in a state where the workpiece is disposed between the spacer plate and the pushing body.

(7) In (4) or (5) or in (6) citing (4) or (5), preferably, the connecting portion holds the spacer plate and the pushing body such that the spacer plate and the pushing body do not contact the workpiece before the second member closes the open end of the recess, and holds the spacer plate and the pushing body in contact with the workpiece once the second member has closed the open end of the recess.

(8) In (5), the fixing mechanism preferably includes an elastic body for pushing the spacer plate in a direction heading away from the second member.

(9) In any of (1) to (8), the positioning mechanism preferably includes: a first moving body that projects into the housing space and supports the workpiece in a predetermined position in a projection direction of the first moving body; and a second moving body that projects into the housing space such that the second moving body faces the first moving body, and pushes the workpiece toward the first moving body.

(10) In (9), the first moving body and the second moving body preferably penetrate the first member.

(11) In (9) or (10), the first moving body preferably includes a rod that is caused to extend and retract by a numerical value control actuator.

(12) In any of (1) to (11), preferably, the chamber further includes a nozzle, and the positioning mechanism positions the workpiece in a position where the nozzle can be attached to the opening.

(13) A lid according to another aspect of the present invention is a lid for use on a chamber for a leak tester, the chamber housing a workpiece having an opening, the lid including: a lid body that is adapted to close an entrance or exit through which the workpiece is inserted into or removed from the chamber; a spacer plate disposed on an inner surface side of the lid body such that an interval is formed between the spacer plate and the lid body; and a pushing body disposed on the inner surface of the lid body such that the workpiece can be sandwiched between the pushing body and the spacer plate.

(14) A leak tester according to a further aspect of the present invention includes a chamber housing in the interior thereof a workpiece having an opening, the chamber including: a first member having a recess that forms a housing space for the workpiece; a second member adapted to close an open end of the recess; and a positioning mechanism for positioning the workpiece within the housing space such that the opening is in a predetermined position, wherein the positioning mechanism holds the workpiece apart from the first member and the second member.

In the chamber according to an aspect of the present invention, the positioning mechanism is capable of positioning the workpiece apart from the first member and the second member, and therefore the housing space does not have to correspond to the size of the workpiece. As a result, workpieces of different sizes can be positioned within the housing space of the chamber.

Embodiments of the present invention will be described in detail below with appropriate reference to the figures. Note that the figures are schematic and may not correspond to actual dimensions, ratios, and so on.

Chamber

A chamberofis a chamber used in a leak tester. The chamberhouses in the interior thereof a workpiecehaving an opening. The workpieceis a hollow body, for example. There are no particular limitations on the shape of the workpiece, but for example, the workpiecemay be formed in a shape having two parallel surfaces (a first surfaceand a second surface), with the openingprovided in a surface (a third surface) that connects the first surfaceto the second surface. The chamberis provided to allow the workpieceto be inspected for leakage of a fluid such as a tracer gas sealed inside the workpiece.

The chamberincludes a first memberhaving a recessthat forms a housing space S for the workpiece, a second membercapable of closing an open end of the recess, and a positioning mechanismfor positioning the workpiecewithin the housing space S so that the openingis in a predetermined position. By closing the open end of the recessusing the second member, the housing space S is configured as a hermetically sealed space.

The chamberalso includes a nozzle. The nozzleprojects into the housing space S through the first member. The nozzleprojects in a direction perpendicular to a depth direction of the recess. In other words, the nozzleprojects in a direction parallel to the outer surface of the first memberon which the recessis open (more specifically, an end surface on an open side of a peripheral wall portion, to be described below). The nozzleis configured to be capable of advancing and retreating in an axial direction. The fluid is sealed inside the workpieceby attaching the nozzleto the openingwithin the housing space S.

The positioning mechanismholds the workpieceapart from the first memberand the second member. The positioning mechanismincludes a first positioning mechanismfor positioning the workpiecein the depth direction of the recess, and a second positioning mechanismfor positioning the workpiecein a direction other than the depth direction of the recess

The positioning mechanismpositions the workpiecein a position where the nozzlecan be attached to the opening. In other words, in the chamber, the workpieceis positioned within the housing space S by the positioning mechanismin alignment with the position of the nozzlewhile keeping the placement of the nozzleconstant. According to this configuration, workpiecesof different sizes can easily be positioned in desired positions within the housing space S. As a result, leak tests can easily be performed on workpiecesof different sizes.

In the chamber, the positioning mechanismis capable of positioning the workpieceapart from the first memberand the second member, and therefore the housing space S does not have to correspond to the size of the workpiece. Accordingly, in the chamber, workpiecesof different sizes can be positioned within the housing space S.

The respective constituent members of the chamberwill be described in detail below.

First Member

As shown in, the first memberincludes the tubular peripheral wall portionand a bottom wall portionthat closes an opening at one end of the peripheral wall portion. The peripheral wall portionhas a rectangular tube shape, for example. The recessis defined by the inner surface of the peripheral wall portionand the inner surface of the bottom wall portion. The recesshas a rectangular parallelepiped shape, for example.

Second Member

The second memberis configured to be capable of closing the open end of the recess, as described above. In other words, the second memberis a lid body capable of closing an entrance/exit through which the workpieceis inserted into/removed from the chamber. The second memberis plate-shaped. The second memberis configured so that a peripheral edge part of the inner surface thereof can be appressed to the open-side end surface of the peripheral wall portion. The inner surface of the second memberdefines the housing space S for the workpiecetogether with the inner surface of the recess. Note that the “inner surface” of the second member refers to the surface on the side that faces the housing space S in a state where the open end of the recess is closed.

A sealing member for maintaining air-tightness may be disposed on the appressed parts of the first memberand the second member. For example, the sealing member may be attached in advance to one or both of the open-side end surface of the peripheral wall portionof the first memberand the peripheral edge part of the inner surface of the second member. An O-ring, for example, may be used as the sealing member.

First Positioning Mechanism

As shown in, the first positioning mechanismincludes a spacer plateand a pushing body, which are respectively disposed on the second member. The first positioning mechanismalso includes a connecting portionfor connecting the spacer plateto the second member. In this embodiment, the spacer plateand the pushing bodyface each other in a horizontal direction.

The first positioning mechanismis housed in the housing space S together with the workpiecein a state where the workpieceis disposed between the spacer plateand the pushing body. In other words, the second memberis configured to be capable of closing the open end of the recessin a state where the workpieceis disposed between the spacer plateand the pushing body. According to this configuration, the workpiececan easily be inserted into and removed from the housing space S of the chamber, and the workpiececan be positioned within the housing space S easily and reliably.

Spacer Plate

As shown in, the spacer plateis interposed between the workpieceand the inner surface of the recess, or more specifically between the first surfaceof the workpieceand the bottom surface of the recess. The plate thickness of the spacer plateis adjusted so that the positions of the openingof the workpieceand the nozzleare aligned in the depth direction of the recess. A flow passage through which the fluid that leaks out from the workpiececan pass may be formed in the spacer plate. There are no particular limitations on the flow passage, but a groove formed in the surface that faces the workpiece, for example, may be used. Alternatively, the flow passage may be formed by providing a ventilation portion formed from a porous material or the like in the spacer plate.

The spacer platehas a rectangular shape when seen from the plate thickness direction, for example. The spacer plateincludes a bodydisposed on the side facing the bottom surface of the recess, and an auxiliary portionthat is laminated onto the bodyso as to face the workpiece. The auxiliary portionmaintains the position of the workpiecewhile absorbing deformation of the workpiecewhen the workpieceis caused to expand by the fluid sealed therein or the like.

Pushing Body

The pushing bodyis disposed so as to face the spacer platewith the workpiecetherebetween. In other words, the pushing bodyis interposed between the second surfaceof the workpieceand the inner surface of the second member. The pushing bodyis plate-shaped, for example. The pushing bodyis provided so as to be capable of pushing the workpiecetoward the spacer plateside. The pushing bodyis supported from the second memberside by a spring membersuch as a coil spring. In a state where the workpieceis housed in the housing space S, the spring memberbrings the second surfaceof the workpieceinto contact with the pushing bodyand pushes the spacer platetoward the bottom surface side of the recessvia the workpiece. A flow passage through which the fluid that leaks out from the workpiececan pass may be formed in the pushing body. There are no particular limitations on the flow passage, but for example, a groove, a ventilation portion, or the like similar to that of the spacer platemay be used.

The first positioning mechanismincludes the spacer platethat is interposed between the workpieceand the bottom surface of the recess, and the pushing bodythat faces the spacer platewith the workpiecetherebetween, and the pushing bodyis capable of pushing the workpiecetoward the spacer plateside. Thus, the first positioning mechanismcan easily hold the workpieceapart from the first memberand the second member.

By pushing the spacer platevia the workpiece, the pushing bodyappresses the spacer plateto the bottom surface of the recess. In other words, according to the chamber, the workpieceopposes the bottom surface of the recessvia an interval corresponding to the plate thickness of the spacer plate. In the chamber, therefore, the interval between the bottom surface of the recessand the workpiececan be controlled on the basis of the plate thickness of the spacer plate. Hence, as shown in, for example, by adjusting the plate thickness of the spacer platein accordance with the placement of the openingin the workpiece, workpiecesof different shapes and different sizes can be housed in the chambereasily and with stability. Note that there are no particular limitations on the method for adjusting the plate thickness of the spacer plate, and for example, the plate thickness may be adjusted by varying the thickness of one or both of the bodyand the auxiliary portion

Connecting Portion

The connecting portionholds the spacer platein a cantilevered manner. The connecting portionholds the spacer platein a linear manner along the outer edge of the spacer plate, and more specifically holds the spacer platein a linear manner along the lower edge of the spacer plate. By using the connecting portionto hold the spacer platein a cantilevered manner, as described above, the workpiececan easily be disposed between the spacer plateand the pushing body. Moreover, according to this configuration, the spacer platecan easily be appressed to the bottom surface of the recess

The connecting portionis preferably provided on the outside of the path taken by the workpiecewhen the workpieceis disposed between the spacer plateand the pushing body. The chamberincludes a placement standthat supports the workpiecefrom below when the workpieceis disposed between the spacer plateand the pushing body. The placement standis connected to the second member, for example. The connecting portionconnects the spacer plateand the second memberin a position (in this embodiment, on the lower side of the placement stand) that does not impede placement of the workpieceon the placement stand. According to this configuration, the workpiececan be disposed and extracted quickly, easily, and reliably.

As shown in, the connecting portionincludes a swinging mechanismcapable of swinging the spacer plate, and a fixing mechanismcapable of maintaining the interval between the spacer plateand the workpiece. More specifically, the connecting portionincludes a pair of swinging mechanismsthat are arranged with an interval therebetween so as to be connected on the respective sides of the spacer plate, and fixing mechanismsthat respectively form pairs with the swinging mechanismsare disposed on the respective sides of the spacer plate. In the chamber, by providing the connecting portionwith the swinging mechanismsand the fixing mechanisms, the spacer platecan be controlled to be in a swingable state and a state of being fixed in a predetermined position. As a result, by fixing the spacer platewhen the workpieceis to be disposed between the spacer plateand the pushing body, for example, unintentional contact between the spacer plateand the workpiececan be suppressed. Furthermore, by making the spacer platecapable of swinging in a state where the workpieceis housed in the chamber, the spacer platecan easily be appressed to the bottom surface of the recess

The swinging mechanismis rod-shaped, for example. The swinging mechanismis connected to the spacer plateand the second memberat respective longitudinal direction ends thereof. The swinging mechanismhas a rotary shaft X that serves as the swinging center of the spacer plate. The rotary shafts X provided on the pair of swinging mechanismsare positioned coaxially.

Further, the swinging mechanismincludes an expandable portioncapable of varying the interval between the spacer plateand the second member. The expandable portionhas a spring member such as a compression spring. The expandable portionis normally held in an expanded state. The expandable portionis configured to be capable of contracting so that when the second memberis pushed toward the spacer plateside in a state where the spacer plateis supported by the bottom surface of the recess, the pushing bodycan be pushed against the workpiece.